McCullough initially maintained that she stands by the Schapiro Group study, in part because she has been told that "it is the same scientific methodology that science has been using for a long time to measure endangered species."

But when pressed on whether she really believes that counting Internet photos is reliable, she grants the sex-work industry isn't exactly the gold standard of truth in advertising.

"That's absolutely correct," she says. "That's part of how that business operates: It's a bait and switch."

Jesse Lenz

Deanna Dent

Steve Doig, the Knight Chair in Journalism at Arizona State University, says the Schapiro study is based on a logical fallacy.

Details

EDITOR'S NOTE: Village Voice Media, which owns this newspaper, owns the classified site Backpage.com. In addition to used cars, jobs, and couches, readers can also find adult ads on Backpage; for this reason, Women's Funding Network and their allies have often called attention to the site, sometimes going so far as to call for its closure.

Certainly we have a stake in this discussion. And we do not object to those who suggest an apparent conflict of interest. We sat quietly and did not respond as the WFN held symposiums across America—from Seattle to Miami—denouncing Backpage. Indeed, we were never asked for response.

But then we looked at the "science" and the media's willingness to regurgitate, without question, these incredible statistics. In the interest of a more informed discussion, we decided to write.

And given the tricky nature of the photographs, she admits that counting pictures isn't exactly a precise way to measure juvenile prostitutes.

"I can't guarantee that any picture, that four of those six people said looked young — that may not be the girl that you'd get if you called up," she concedes.

Asked if she has any reason to believe that the six observers in the study have the identical 38 percent error rate as the 100 random citizens who were the initial test subjects, she allows that it might be worth revisiting that question.

The basic truth is that the study exists in service of the advocacy, and if news outlets present the Schapiro Group's numbers as gospel, it certainly doesn't hurt the advocates' cause.

Admitting that there isn't any authoritative scientific count of juvenile prostitution, as Finkelhor recommends, isn't an option in McCullough's book. She recalls an early presentation she made in Nebraska, when a politician gave her a piece of advice that stuck.

"He said, 'If you all as a movement don't start having numbers, you are going to lose the money,'" McCullough recalls. "'How can you justify millions of dollars when there are only hundreds of victims that you're actually serving?'"

Editor's Conclusion: Last week, on March 16, the drumbeat continued in the U.S. Senate with a briefing on domestic minor sex trafficking that featured Hollywood actress Mira Sorvino and the startling statistic that 100,000 children are trafficked for sex annually in America.

Trafficking, in labor and sex, became a defining issue in the administration of President George W. Bush. But as an investigation by the Washington Post in 2007 revealed, victims in the sex trade were difficult to come by.

Today, advocates have shifted media attention to allegations of trafficking in children.

But facts to suggest a plague of underage perversion simply do not exist despite claims to the contrary.

In a deficit-obsessed Congress, there is a long line of those seeking tax dollars to raise awareness of trafficking: government agencies, nonprofits, religious groups, the well-intentioned, as well as abolitionists opposed to everything from pornography to adult services.

It is no surprise that some seek to use children as a wedge.

Responsible parties prosecute predators and rescue victims. Not everyone with a microphone is responsible.

The challenge of keeping children out of the hands of exploiters is real, but solutions are not clear in an atmosphere of hyped hysteria.